A new study has found a concerning link between excessive TV viewing and an increased risk of dementia, Parkinson’s disease, and strokes. The research, conducted by Tianjin Medical University in China, analysed data from over 400,000 UK adults with an average age of 55.8 to investigate the impact of recreational screen time on brain health. The results, published in the Journal of the American Medical Directors Association, revealed that watching TV for more than five hours a day significantly raised the risk of developing these serious conditions.
Of the participants studied, 61% reported between one to four hours of screen time per day. The average TV watching time was 2.7 hours, while computer screen time for recreation averaged 1.1 hours. Individuals who watched between three to five hours of TV daily had a 15% increased risk of developing dementia compared to those who watched one hour or less. Shockingly, those who spent over five hours in front of the television faced a 44% higher risk of dementia, a 12% increased risk of stroke, and a 28% higher risk of Parkinson’s disease.
Interestingly, the study did not find any increased risk associated with excessive computer screen time, which is often linked to more mentally engaging activities. The researchers noted that prolonged TV viewing was linked to reduced grey matter and smaller memory centres in the brain, both indicators of potential brain diseases. Although the exact mechanism behind this link remains unclear, it is hypothesised that sedentary behaviour associated with TV viewing, such as low muscle activity and circulation, may contribute to chronic inflammation and decreased blood flow to the brain.
The researchers recommended limiting daily TV viewing time to three hours as it showed the most beneficial outcomes in reducing the risk of brain-related disorders. These findings highlight the importance of managing recreational screen time, especially TV viewing, to promote better brain health and overall well-being. The study sheds light on the potential consequences of excessive sedentary behaviours and underscores the need for public health interventions to address the impact of screen time on brain function.